エキシマレーザーによる冠動脈内視鏡視下手術

補助循環を用いた心拍動停止下手術の可能性

抄録

The research for the endoscopic coronary laser angioplasty system using excimer laser and a very thin diameter endoscope has been performed since 1987 by us. To date, the laser endoscopic system, which is able to approach into the coronary artery percutaneously, could be developed. However in-vivo study showed that there remained the following problems; 1) it was impossible to make the laser aiming under the moving visual field caused by the beating of the heart, 2) it was impossible to perform the operation successfully within a few minutes of manipulation inside coronary because of the ischemie of the heart.
In order to improve these problems, we tried to examine the possibility of the procedure in the arrested heart by using the circulatory assistance.
The PCPS system was used for the circulatory assistance. The endoscopic coronary laser angioplasty system consist of the long-pulse excimer laser (308nm wave length, 8Ons pulse duration) and the ultra-thin laser endoscope (1.5mm diameter) for the coronary artery was used for the experiment. The endoscope had the 4-directional bending function at the tip.
Four goats with about 50kg weight were used. When the heart was beating, it was impossible to aim the target with the laser. However, when the heart was arrested under the circulatory assistance, the target could be aimed successfully with laser. The arrested heart was begun to beat again with the DC shock after the examination. In the experiment of the endoscopic coronary laser angioplasty, the heart was arrested immediately after the insertion of the skin tissue into the coronary artery by the acute myocardial infarction. Under the circulatory assistance, the excimer laser did not failed to be aimed to destroy the obstruction. However, the length of the obstruction was too long to remove the obstruction completely. The safety and reliable endoscopic coronary laser angioplasty would be possible, if the safety cardiac arrest condition was obtained in future.